The present invention relates to delayed-tackifier coated particulates and methods relating thereto.
Particulate packs are often used in wellbore operations to enhance the flow of fluids while mitigating the flow of particulates (e.g., formation fines and particulates from the pack). To further aid in the mitigation of particulate migration, the particulates of the particulate packs are often coated with tackifiers that allow for migrating particulates to stick thereto. As used herein the term “tackifier” generally refers to a chemical or polymer capable of forming a nonhardening coating on a surface of a particulate (e.g., formation fines, proppant particulates, and gravel particulates).
Generally, traditional tackifiers are sticky to the touch, which often causes the coated particulates to accumulate on surfaces of wellbore tools (e.g., pumps, pipes, sand screws, and the like). Cleaning the wellbore tools can often be a time-consuming undertaking that may involve the use of expensive chemicals. In some instances, if the accumulation of particles is too high, the wellbore tools may be damaged and need repair or replacement. For example, operating equipment may jam resulting from buildup of coated proppant during the fracturing treatment, causing delay of proppant transport and potentially shut down of the operation.
Additionally, in deviated wellbores, the accumulation of tacky particulates can be especially problematic because particulate settling is magnified across the wellbore radius as compared to along the wellbore length. As the particles settle, the tackifier can cause the particles to accumulate into larger masses that can eventually cause the pressure in the wellbore to increase, which can lead to costly formation damage. In horizontal well gravel packing or multi-stage fracturing treatments, settled sand or proppant forms dunes in the wellbore which may lead to premature screenout. The remediation of accumulated particulates in a deviated wellbore may be especially time-consuming and costly.